The field of this invention is pipe handling systems and in particular, a system for handling pipe on a vessel.
Vessels, both barges and ships, for laying an underwater pipeline are known. Generally, such vessels include a pipe laying station on the deck where pipe lengths are successively attached to the portion of the pipeline already laid, the ship simply moving forwardly each time a pipe length is attached to the pipeline so that the pipe laying station is free to receive another pipe length for attachment to the pipeline.
Since the pipeline is to be under water, the pipe lengths are in most cases weight-coated with concrete or the like before they are placed on the vessel. Thus, each pipe length, which may for example be 60 feet long and 5 foot in diameter, is extremely heavy. It is desirable to use pipe laying vessels with large hold so that large numbers of pipe lengths can be stored. A problem with storing pipe lengths below deck is the difficulty encountered in raising such heavy pipe lengths out of the hold and into position on the deck while the ship may be moving in pitch, roll and yaw due to the forces exerted by wave action.